PCA9540BGD,125

Product Overview

• Category: Integrated Circuit
• Use: I2C Multiplexer
• Characteristics: Low-voltage 4-channel I2C multiplexer with reset
• Package: TSSOP16
• Essence: The PCA9540BGD,125 is a multiplexer that allows multiple I2C devices to share the same I2C bus. It provides a simple solution for expanding the number of I2C devices that can be connected to a microcontroller or other I2C master device.
• Packaging/Quantity: The PCA9540BGD,125 is typically sold in reels containing 2500 units.

Specifications

• Supply Voltage Range: 1.65V to 5.5V
• Number of Channels: 4
• I2C Bus Compatibility: Standard-mode, Fast-mode, Fast-mode Plus
• Reset Function: Yes
• Operating Temperature Range: -40°C to +85°C

Pin Configuration

The PCA9540BGD,125 has a total of 16 pins arranged as follows:

```

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| | | 1 8 9 | | | | 16 15 14 | |___________________| ```

Pin Description:

1. SCL0: I2C clock input/output for channel 0
2. SDA0: I2C data input/output for channel 0
3. GND: Ground
4. SCL1: I2C clock input/output for channel 1
5. SDA1: I2C data input/output for channel 1
6. VCC: Power supply voltage
7. RESET: Active-low reset input
8. SCL2: I2C clock input/output for channel 2
9. SDA2: I2C data input/output for channel 2
10. NC: No connection
11. SCL3: I2C clock input/output for channel 3
12. SDA3: I2C data input/output for channel 3
13. A0: Address selection bit 0
14. A1: Address selection bit 1
15. A2: Address selection bit 2
16. GND: Ground

Functional Features

• Allows multiple I2C devices to share the same I2C bus
• Supports standard-mode, fast-mode, and fast-mode plus I2C bus compatibility
• Provides a reset function for all channels
• Low-voltage operation allows compatibility with a wide range of microcontrollers and other I2C master devices

Advantages and Disadvantages

Advantages: - Enables efficient utilization of the limited number of I2C bus pins on microcontrollers - Simplifies I2C bus management in systems with multiple I2C devices - Low-voltage operation enhances compatibility

Disadvantages: - Requires additional control logic to select the desired channel - Limited to 4 channels, may not be suitable for systems with a large number of I2C devices

Working Principles

The PCA9540BGD,125 operates by selectively connecting one of its four I2C channels to the shared I2C bus. The desired channel is selected using the address selection bits (A0, A1, A2). When a channel is selected, the corresponding SCL and SDA pins are connected to the I2C bus, allowing communication with the devices connected to that channel. The reset function can be used to reset all channels simultaneously.

Detailed Application Field Plans

The PCA9540BGD,125 finds applications in various scenarios where multiple I2C devices need to be connected to a single I2C bus. Some potential application fields include:

1. Sensor Networks: In sensor networks, multiple sensors can be connected to the same I2C bus using the PCA9540BGD,125, simplifying the wiring and reducing the number of required I2C pins on the microcontroller.
2. Industrial Control Systems: The PCA9540BGD,125 can be used in industrial control systems to connect multiple I2C-based control modules to a central controller, enabling efficient communication between different modules.
3. Embedded Systems: In embedded systems, where space is often limited, the PCA9540BGD,125 allows for the expansion of I2C device connectivity without requiring additional I2C buses or microcontrollers.

Detailed and Complete Alternative Models

Some alternative models that offer similar functionality to the PCA9540BGD,125 are:

1. PCA9541PW,112: 2-channel I2C multiplexer with reset
2. PCA9542APW,118: 4-channel I2C multiplexer without reset
3. TCA9548APWR: 8-channel I2C